Chemistry and the Scientific Method

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Chemistry and the Scientific Method
Chapter 1
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Chemistry

• Why is it important to learn chemistry?
• Its important to learn chemistry
• To become a scientist.
• For careers Medical, forensics, environmental,
  agricultural, engineering
• To make decisions about technology and the
  environment.
• Understand important issues

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What is chemistry?

• What are three things you think of when you hear
  the word chemistry?

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What is chemistry?

• Why do leaves turn colors in fall?
• Why does iron rust?
• What makes fireworks change colors?
• What happens inside a battery?

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World Issues

• In groups, list main problems in the world
  (hunger, disease, etc.). Then write on the board
  and circle which ones have to do with chemistry.

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The Scientific Method.

• Observation Recognize a problem or notice
  something happening.
• Example You saw Mr. X outside KFC on Monday.
• Hypothesis Propose a solution or explanation.
• Example Mr. X eats at KFC on Mondays.
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• Experiment Test your hypothesis to see if it is
  true. This leads to a new observation!
• You can accept or reject your hypothesis.
• If you reject your hypothesis, you can revise it
  and test it again.
• If you accept your hypothesis, you do more
  experiments to build up more evidence for your
  hypothesis.

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• Experiment (Continued)
• Example How can you test the hypothesis that Mr.
  X eats at KFC on Mondays? What data would
  support your hypothesis? What data would lead
  you to reject your hypothesis?

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The Scientific Method.

• After the process is repeated, you can collect
  the hypotheses into a theory. A scientific
  theory explains the behavior of nature. A theory
  answers the question why?
• A natural law summarizes behavior, but does not
  explain why it happens.
• A theory does not become a law.

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The Scientific Method

• Every day you bring a delicious chocolate bar to
  school. One day, it is gone when you want to eat
  it at lunch. The next day, the same thing
  happens.
• Make a hypothesis about what happened to the
  chocolate and design an experiment to test the
  hypothesis.

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• If something is scientifically proven, it doesnt
  mean its true. Scientific theories can be
  proven to be incorrect.
• Example When scientists were studying the
  structure of DNA, Linus Pauling proposed that DNA
  had a triple helix. Later, Watson and Crick
  showed that it was a double helix. 

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• Scientific explanations must meet certain
  criteria they should be logical, respect the
  rules of evidence, be open to criticism, report
  methods and procedures, and make knowledge
  public.

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• Before a research report is published in a
  scientific journal, it must be peer-reviewed.
• This means that other scientists in the same
  field must read and approve of the report.

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The Scientific Method

• Classify the following as an observation, theory
  or law.
• Mr. Bly eats an egg and vegetable sandwich every
  day.
• Mr. Bly eats sandwiches because they are very
  delicious.
• I saw Mr. Bly eating a sandwich yesterday at 5
  pm.